Prior to producing hydrocarbons from a geological formation it is common to place a casing in the formation and to inject cement into an annulus between the casing and the formation in order to cement the casing in place. Holes in the casing and cement are made to establish fluid connectivity between the formation and the wellbore. The integrity of the cement in the annulus is important, and acoustic evaluation of the cement can be used to determine the integrity of the cement and to further determine whether the cement is providing hydraulic zonal isolation between formation strata traversed by the drilled well (borehole). Failed zonal isolation can lead to significant environmental consequences as well as to compromising the economic viability of the production well.